成都市土壤中有机磷阻燃剂的污染特征及来源分析

Pollution characteristics and sources of OPEs in the soil of Chengdu City

在建立土壤中痕量有机磷酸酯阻燃剂（OPEs）的GC-MS实验室分析方法基础上,定量分析了成都市主城区表层土壤中7种典型OPEs（磷酸三丁酯（Tn BP）、磷酸三异辛酯（TEHP）、磷酸三丁氧乙酯（TBEP）、磷酸三苯酯（TPh P）、磷酸三氯乙酯（TCEP）、磷酸三氯丙酯（TCPP）、磷酸三（2,3-二氯丙基）酯（TDCPP））的含量及分布特征,采用插值法和聚类分析研究其空间分布,运用相关性分析和正定矩阵因子分解法对土壤中OPEs的来源进行了探析.结果表明,成都市主城区表层土壤中7种OPEs（∑7OPEs）的含量水平在31.6~211 ng·g^-1之间,算术平均值为99.9 ng·g^-1.所有样品中TBEP均为含量最高的单体,其含量占∑7OPEs总含量的52%~92%.从空间分布来看,成都市西北至东南沿线为OPEs的主要分布带,三环外东北和西南则为OPEs的低值带.聚类分析结果表明,OPEs的谱特征与上述空间分布特征具有一致性,可分为2类地区：第1类地区位于主要分布带,属高值区（∑7OPEs平均值为133.1 ng·g^-1）,第2类地区位于低值区（∑7OPEs平均值为60.2 ng·g^-1）.两类地区的谱特征差异主要体现在TCEP与TBEP的百分含量上.相关性研究表明,Tn BP与TCEP之间可能有较强的同源性,TBEP、TPh P、Tn BP三者之间也可能具有较强的同源性,而TEHP与其他种类OPEs可能不具有同源性.正定矩阵因子分解结果表明,OPEs主要来源有2个,不饱和聚酯树脂产品制造业、建筑物装潢/室内源对成都市土壤中OPEs的贡献率分别为43%和57%.

Seven types of typical organophosphates ester（ OPEs） in the surface soils of urban Chengdu,including Tri-n-butyl phosphate（ Tn BP）,Tris（ 2-ethylhexyl） phosphate（ TEHP）,Tributoxyethyl Phosphate（ TBEP）,Triphenyl Phosphate（ TPh P）,tri（ 2-chloroethyl） phosphate（ TCEP）,Trichloropropyl phosphate（ TCPP） and Tridichloropropyl phosphate（ TDCPP）,were measured using GC-MS. Spatial distribution of these compounds was analyzed using interpolation and clustering method,and their sources were identified using correlation and positive matrix factorization（ PMF） methods. The pollution levels of the total OPEs（ ∑7OPEs） in the urban surface soils ranged from 31. 6 ng·g^-1to 211 ng·g^-1with the mean of 99. 9 ng·g^-1. TBEP dominated the profile in all soil samples and accounted for 52% ~ 92% of the ∑7OPEs. Samples with high concentrations were found in the area from northeast to southeast with the mean level of 133. 1 ng·g^-1,and the samples with low levels were only observed in the northeast and southwest areas outside of the third ring road with the mean level of 60. 2 ng·g^-1. The areas with high and low levels were consistent with those of cluster analysis characterized with two typical groups. The relative contributions of TCEP and TBEP were different in the two groups. The correlation studies showed that Tn BP and TCEP probably had similar sources while TBEP,TPh P and Tn BP likely came from other similar sources. However,TEHP and other OPEs may not come from similar sources. The results of PMF showed that OPEs were mainly from the production progress of unsaturated polyester resin and decoration / indoor sources,contributing 43% and 57% to the OPEs in Chengdu urban surface soils,respectively.